BrazzleAZ

I am posting to hopefully figure out quickly the process and parts needed for the AC related issues I have. First issue is the 2 passenger front vents blow slightly cooler than warm while the driver side is cold. I have read there are servos behind the glovebox that control this function, 1 of the 3 is for those vents. I am having a hard time finding out which one of those 3 it is, and a part number so I can try and find it local to do this weekend (memorial day weekend). I have seen the write up somebody did but none of the pictures in the steps show and it's from many years back. I also saw a write up on taking them apart and cleaning them and then they work. I can try that as well, I would just like some help figuring out which servo it is I need to pull. I haven't noticed any clicking noises personally, but I bought the car for a struggling family member a few days ago and want to fix this problem for them ASAP.

The other issue is the AC doesn't seem to be as cold as it should. Haven't out a thermometer in the vent yet, but comparing to other Toyotas, as well as other gs300 owners and the AC is definitely not as cold as it can be. I hooked my AC gauges up and the high side and low side are equal to each other before starting. Roughly 100 degrees yesterday. After starting, high side goes to around 200-210 and low side was around almost 100. When I tried to hook them up yesterday, for some reason I struggled to get the fitting on the low side, and I bumped the valve stem a few times. When I eventually got it hooked up, it was now reading about 35 ish. I was thinking expansion valve or it just got over charges by the previous owner. But the low side being bumped down didn't seem to have an effect on the temperature, negative or positive. Compressor appears to function correctly. And it takes awhile to get as cold as it gets. Most cars, it will at least be cool to cold even here in the summer within a minute or 2. And then take awhile to get comfortable. But this took between 10-15 minutes of driving for it to really get cold. I've never had a vehicle do that before.

I'm taking the car back for the extended weekend and hoping to have it fixed by then. I pretty much have to have it done, so I was hoping somebody here can at least point me in the right direction. I currently don't have the car, and won't for a few days, so unfortunately I don't know how much more information I have at this time.

SaiyanGS3

iTrader: (8)

This thread has everything you need. It sounds like you have issues with the driver’s side AC servo motor. The photos are gone; the OP was kicked off this site so he took all of his DIYs down. Google the name to get the part numbers.

https://www.clublexus.com/forums/gs-...r-rebuild.html

BrazzleAZ

So according to the diagram at the end of that thread, the passenger mix servo( the one I'm assuming is the issue since the air is warm coming out the passenger side vents only) is on the driver's side, and not the passenger side? So they flipped the driver side and passenger side on at factory for some reason?

I can adjust the heat up to 85 and it gets pretty got then bump it back down and it cools down but doesn't get anywhere near as cold as the driver side.

Also, the Lexus GS300 is the same color and looks exactly like the one in your sig.

BrazzleAZ

It ended up not being the passenger side mix/blend servo. I watched them before getting started and saw it move from one end to the other, correctly, as well as the other servos.So the only other thing it could be was the low refrigerant that was only getting cold enough to let cold air out the driver side (because that's the side the evap is, and air is cold there first). So, i replaced the expansion valve and pulled vacuum for an hour and a half, then let it sit for almost an hour and it was perfect. So i recharged the system. (discovered another issue right when this happened, but that's in another post of mine.) After the recharge, the ac not only comes out cold on the passenger side, it is substantially colder now than it was before. I checked with a thermometer and I got as low as 59 degrees, so I know it's working great.

BrazzleAZ

ok so I am back, now in the same boat I think.

I drove the car for maybe 20 miles today, and it started cutting the ac out. So i got home, turned it off, hooked my gauges up, and it was working again. I was like, that's odd. So i started looking everything over, didn't hear any massive leaks. Compressor kicks on and off as it should. It gets cold. Then, when I rev it, the low side pressure shoots up, and then it gets hot again. Compressor engaged the entire time. When the rpms come back down, it starts to get cold again. I put some cheap parts store special expansion valve in so I think that is defective.

Anybody have any idea on where I can find an OEM expansion valve? I called lexus local here in phoenix and they want $176 for one. Really don't want to shell out that much for the expansion valve.
Lexus gave me part # "88515-22260" for my make and year (2002 GS300). The part number that's on the expansion valve apparently isn't how lexus classifies it. It's a Denso part number, but not Lexus's I guess. I did find lots of places Denso 475-0506 as the correct expansion valve for this car. I am wondering because this is a Denso brand product, it's trust worthy. Denso is the OEM brand for the expansion valve, and both part numbers are expansion valves for the gs300 when i check everywhere online. Anybody got any ideas?

rgrant159

Wanted to bump this... I have a 01 gs300. When the a/c is on 65.. the passenger blows hot air. I've checked the passenger servo, pulled and cleaned it. It no longer makes the grinding noise.

I am thinking it maybe the expansion valve as well. Does anyone have any updates?

BrazzleAZ

So the servos on mine didn't make an abnormal noise and operated just fine. So I replaced the expansion valve. I thought I fixed it but then it just kept happening. I literally had no idea what it could have been and after spending almost an entire day searching online I was desperate. I did see somebody say somewhere that you really should only use OEM. On AC components I didn't think it mattered. Turns out, I was wrong.

It was the expansion valve all along, and a new one the first time didn't fix it because it was some off brand I bought. I can't remember where I bought it from but it wasn't an OEM one. Also, it's extremely confusing to figure out which one is the correct one. The dealer number is not what you need. It's been updated and it's a shorter number now. I can't remember what it was, but I want to say it was an ac Delco and it was 2 sets of numbers with a dash in between them. I was nervous because I didn't feel confident about it but ordered it anyways. I believe I got it from summit racing. But once you have the part number I think multiple places carry it.

Expansion valve is also pretty easy to replace. If you haven't seen the videos, just Google it. There's a video I think of a gs430 but it's the same. You scrape the stuff off around it, then I believe there are 2 bolts, then carefully pry at it as much as you can around it and then it will break free. Make sure you evacuate and ac first because if you don't you are risking injury and getting sick. When it breaks free, some will still leak out from the pressure but you will be fine. You will have to carefully bend it back to pull the valve out, which is like 1" x 1" x 3" roughly. Kind of built like a jenga block.

Put the new one in, and carefully try to bend the hose back over it and start the bolts. Once those are tightened all the way, get your vacuum pump set up and pull vacuum. Do yourself a favor and buy an electric vacuum pump. Yes pneumatic ones work but the cheap electric vacuum pump from harbor freight is worth it. Trust me on this, makes everything much easier. Pull vacuum for 2-3 hours just to make sure, then let it sit for awhile too to ensure it doesn't drop. If it drops noticeably you have a leak and should double check those bolts. No drop, means you're ready to recharge your ac. I won't go into that because that's been documented tens of thousands of times on the internet.

The reason I got this in depth in my response wasn't just for you. This was in case somebody does a Google search in the future and this thread comes up, there will be a detailed thread about it for them. Summer is here so more people are going to start having AC issues soon and could be needing this.